The present invention relates to a silicon oxide powder and a manufacturing process thereof and a cosmetic preparation, a micelle holding powder, and a perfume holding powder using the same and in particular, relates to an improvement of a shape of the powder.
A so-called mesoporous powder which has a mesopore of 2 to 50 nm pore size attracts attention as an adsorbent of gas or liquid, or as a carrier of a catalyst.
For example, a mesoporous powder which is disclosed in Japanese Unexamined Patent Publication No. Hei 8-67578, is composed of a three-dimensional structure which is made of a silicate and has a uniform pore of 1.5-10 nm in relative.
As for a manufacturing process of the mesoporous powder, a process for forming a three-dimensional structure by introducing a surfactant into an interlayer of a layer silicate such as kanemite and removing the surfactant with calcination or by removing a surfactant after gathering a silicate around the surfactant which was gathered in liquid with micelle state and the like are developed.
However, a particle size of the mesoporous powder is prescribed to the particle size of the layer silicate in the former process which uses the layer silicate. Also, since the mesoporous powder is laminar, it is feared that fluid resistance per pore degree is increased in the case where the mesoporous powder is used as a column packing.
On the contrary, though an examples which manufactured a rod-like porous powders are reported (Science Vol. 273 pp. 765-767), every rod-like porous powders has considerable large size. In particular, an external diameter is approximately 3 xcexcm and a pore size becomes big far from mesoporous in the case where a pure silicic porous powder which is not contained aluminum. Therefore, a specific surface area becomes relatively small and there is a problem that the process is limited to use only for a molecular sceivetic use. Also, a rod-like mesoporous powder of certain fine particle size can be manufactured in the case where aluminum is contained in the powder. However, it is feared that catalytic activity becomes high due to the presence of aluminum. This process is also unfavorable.
In view of the above-mentioned problems of the prior art, a first object of the present invention is to provide a non-laminar silicon oxide powder which is comprised of silicon oxide in practical and has a fine diameter, and a process for manufacturing thereof.
Also, a second object of the present invention is to provide a micelle holding powder which efficiently holds a cationic material.
Further, a third object of the present invention is to provide a perfume holding powder that change of diffusion rate with time is small and that can holds a perfume through a long period of time.
As a result of diligent studies by the inventors for attaining the above-mentioned objects, it has been found that a fine diameter non-laminar silicon oxide powder can be obtained by reacting a silicate which has a specific ratio of silica/alkali metal under a specific concentration. Accordingly, the present invention has been accomplished.
Namely, a non-laminar silicon oxide powder in accordance with the present invention mainly composed of silicon oxide and has almost homogenous pore.
Also, in said powder, it is preferable that said powder is a fine mesoporous powder that a shape of said powder is fine shape and a depth of the pore is 50-300 nm.
Also, in said powder, it is preferable that said powder is a rod-like mesoporous powder that a shape of said powder is rod-like whose outer diameter is 20-200 nm and that a mesopore is elongated to its longer direction in the rod-like mesoporous powder.
Also, in said powder, it is preferable that said powder is a rod-like nonporous powder that a shape of said powder is rod-like whose diameter is 20-200 nm and the powder has no mesopore.
Also, in said powder, it is preferable that a primary particle is formed by aggregating two or more of rod-like substances in network state.
Also, a process for manufacturing a fine mesoporous powder in accordance with the present invention comprises a dissolution step wherein a concentration of 0.1-5.0M of a silicate which is in the range of 0 less than SiO2/Y2O less than 2 (Y: alkali metal atom) is dissolved in the presence of a cationic surfactant and the pH is 11 or more, a condensation step wherein the pH is adjusted to 10.5 or less, a rod-like micelle is formed with said cationic surfactant and a silicate is condensed on said rod-like micelle, and a removal step wherein said cationic surfactant is removed from a micelle state condensation which has an outer shell made of the silicate by said condensation.
Also, a process for manufacturing a rod-like mesoporous powder in accordance with the present invention comprises a dissolution step wherein a concentration of 0.3-1.2M of a silicate which is in the range of 0 less than SiO2/Y2O less than 2 (Y: alkali metal atom) is dissolved in the presence of a cationic surfactant and the pH is 11 or more, a condensation step wherein the pH is adjusted to 10.5 or less within 30 minutes, a rod-like micelle is formed with said cationic surfactant and a silicate is condensed on said rod-like micelle, and a removal step wherein said cationic surfactant is removed from a micelle state condensation which has an outer shell made of the silicate by said condensation.
Also, a process for manufacturing a rod-like nonporous powder in accordance with the present invention comprises a dissolution step wherein a concentration of 1.2-2.0M of a silicate which is in the range of 0 less than SiO2/Y2O less than 2 (Y: alkali metal atom) is dissolved in the presence of a cationic surfactant and the pH is 11 or more, a condensation step wherein the pH is adjusted to 10.5 or less within 30 minutes, a rod-like micelle is formed with said cationic surfactant and a silicate is condensed on said rod-like micelle, and a removal step wherein said cationic surfactant is removed from a micelle state condensation which has an outer shell made of the silicate by said condensation.
Also, in said manufacturing process, it is preferable that said silicate is mainly composed of Na2SiO3.
Also, in a process in accordance with the present invention, it is preferable that said cationic surfactant is a quaternary ammonium salt.
Also, in a process in accordance with the present invention, it is preferable that quaternary ammonium salt: silicate is 1:1-1:50 at molar ratio.
Also, in a process in accordance with the present invention, it is preferable that quaternary ammonium salt: silicate is 1:3-1:20 at molar ratio.
Also, in said process, it is preferable that said quaternary ammonium salt has an alkyl group having a carbon number of more than 18, in the case where a rod-like powder is formed.
Also, in said process, it is preferable that said quaternary ammonium salt has an alkyl group having a carbon number of 18 or less and coexist with 0.1-3M of an acid excluding silicon, in the case where a rod-like powder is formed.
Also, a cosmetic in accordance with the present invention comprises said non-laminar silicon oxide powder.
Also, a micelle holding powder in accordance with the present invention arranges silicate to a micelle outer shell of a cationic material which has surface active ability.
Also, in said micelle holding powder, it is preferable that said cationic material which forms micelle is a quaternary ammonium salt.
Also, in said micelle holding powder, said quaternary ammonium salt which forms micelle has antibacterial activity.
Also a process for manufacturing said micelle holding powder comprises a dissolution step wherein a silicate which is in the range of 0 less than SiO2/Y2O less than 2 (Y: alkali metal atom) is dissolved in the presence of a cationic surfactant and the pH is more than pH 11, a condensation step that the pH is adjusted to 10.5 or less, a rod-like micelle is formed with said cationic surfactant and silicate is condensed on said rod-like micelle.
Also, a perfume holding powder in accordance with the present invention holds a perfume in said mesoporous powder.